Electromagnetic device



W. R. RAY

ELECTROMAGNETI C DEV ICE Filed June 10, 1940 o 19 @K z 5 35 O 38 j v 29 17 mL JAM A. PAY,

INVENTOR.

BY J. fig

ATTORNEY.

Patented Mar. 28, 1944 UNITED STATES PATENT orr cs 2,345,151 ELECTROMAGNETIC DEVICE William E. Bay, Beverly Hills, Calif. Application June 10, 1940, Serial No. 339,765 3 Claims. (01. zoo-an My present invention relates to electromagindicates a base of molded insulating material netic switching devices or relays, and particuon which is mounted, by a right-angle bracket larly to those of the 'sensitive' type wherein a 12, an electromagnet comprising a U-shaped core contact-actuating armature is arranged to be i3 which carries on its free arm ll an energizing attracted, against a bias, by an electromagnet 5 coil ii, the leads it of which are connected to upon the passage through its coil of a small terminals l1 provided on the base. Interposed amount of current -usually direct current or between the bracket l2 and-the supporting arm rectified alternating current. i I8 01 the core is a portion of an armature-retain- -The armature of such a relay is so arranged ing and core-holding member I! of non-magnetic that, when attracted, it is as close as possible to 10 material, having a laterally bent portion pro-' the attracting pole face of the electromagnetcore vided with an opening for receiving the end of without actually being in engagement therethe core arm I and holding it rigidly with rewith. Engagement of the armature and the pole spect to the other arm It The member i9 is face must not be permitted on account of the fully described and claimed in the copending apdanger of magnetic sticking oi the armature l5 plication of William A. Ray, Serial No. 318,520, due to the residual magnetism which remains flled February 12, 1940, which became Patent No. when the core is deenergized. Furthermore, for 2,324,109 on July 13, 1943. 1 maximum sensitivity, the permissible movement: Fulcrumed on the angularly formed end oi oi! the armature, when it is released from its atcore arm It, and guided in an opening iormed in tracted position, must be minute. Consequently, 20 the outer end portion of member i9, is an armathe adjustment of such a relay is delicate and is ture 2|, longitudinal movement oi which is limdifllcult of accomplishment even by a skilled ited by the cooperation of the inner edges of the mechanic. It is therefore an object of my inopening in member IS with notches formed in vention to provide means whereby such a relay the corresponding edges of the armature. A can be fully adjusted by the movement of a single contractile spring 22, connected to the upper part, such as a screw. 1 portion of the armature and to a lug 23 formed A specific object of my invention is the proviby a bent-up portion of member i9 extending sion, in a relay of the character indicated, of a throu h an ope i the c arm L8. urges t e member limiting the movement of the armature lower end 01 the armature away from the pole bothtoward and away from the core and so face or core arm ll.

adjustable as to position the armature with re- Mounted on the base II, by a bracket 24, is In spect thereto. adjusting device, generally indicated at 25 and A further specific object is to provide the aforecomprising a tubular member 26, the reduced said armature-limiting member with a contact left-hand end of which is rigidly secured in an element cooperable with one carried by the armopening in the upper portion of bracket 24.

ature, whereby uniform contact spacing is main- Slidable in the bore of member 26 is a rod 21 tained regardless of the attracted position of the which carries on its outer end a U-shaped memarmature with respect to the core. ber 28, rotation of which is prevented by ears 29 Other objects and advantages. of my invention formed on its inner arm and engageable with the will be found inthe description, the drawing, and a0 edges of bracket 24. Tightly threaded on the the appended claims. inner end of rod 21, and slidable in an enlarged For complete understanding of the invention, portion of the bore of member- 20, is a button 30. reference may be had to the following detailed A spring 3i, compressed between this button and description and accompanying drawing, wherein: the shoulder formed by the enlargement of the Figure l is a plan, with cover removed, of a 5 bore of member 28, urges the rod to the right, relay embodying my invention; movement in that direction being limited by a Figure 2 is a section taken along the line 2-2 plug 32 threaded in the right-hand end of mem-' of Fig. l; her 2 Figure 3 is a detail section of the armature Cooperable with a contact element 33, carried adjusting means of the relay shown in Figs. 1 by the lower end portion of the armature which and 2; and extends between the arms of the U -shaped mem- Figure 4 is a fragmentary view of conventional ber 28, is another contact element 34, pressed in relay adjusting means, shown only for the puran opening in the end of rod 21 which projects pose of comparison. through the inner arm of member 28. Insulat- In Figs. 1-3 of the drawing, the numeral "H at ingly mounted in the 'outer arm oi member. 28

is a stop rivet 35, engageable in the unattracted position of the armature with the riveted-over stem of the armature contact element 33. Means for connecting the switching elements of the relay in,an electrical circuit are provided by a terminal 36, connected by a flexible wire 3'! to i the armature, and by the foot 38 of the bracket 24. Secured to the base II is a metal mounting plate 46 having upturned edges on which a cover or housing 41 is mounted.

To adjust the relay, it is only necessary to move the rod 21 in or out, by turning the screw plug 32, until there is the required gap between the pole face of core arm H and the armature, when the latter is in its attracted position. This gap is usually less than 0.005 inch and may best be determined by the use of a non-magnetic feeler gauge.

The contact gap, or angular distance through which the armature is permitted to move, is fixed and thus remains the same in any adjustment of the relay. As a sensitive relay of the type disclosed is usually only required to control a light load, the wear or burning-away of the contacts is inappreciable. If variation of the contact gap is desired, the stop 35 may be made adjustable. For maximum sensitivity, a contact gap of 0.005 inch or less is usually employed.

As a sensitive relay often loses its adjustment in shipment due to vibration and jar, the simple adjusting means of my invention has particular utility in that it enables the average mechanic to accurately restore the adjustment.

The advantage of the adjusting means which I have provided can best be appreciated by comparison with the conventional adjusting means disclosed in Fig. 4, wherein the numeral 39 indicates the free end portion of a contact-carrying armature which is limited in its movement by a stop screw 40 and a contact screw 4!, threaded in brackets 42 and 43 and locked in adjusted position by nuts 44 and 45, respectively. In ad justing, both nuts are loosened, and the armature properly positioned with respect to its core by movement of the contact screw, after first backing out the stop screw. The contact screw is then looked, care being taken that its position is not disturbed. The contact gap is then similarly adjusted by first moving and then looking the stop screw.

While I have shown the adjusting means of my invention embodied in a simple relay, it is obvious that it also has utility in connection with other types of relays, such as those of the polarized type wherein the armature is repulsed inl stead of attracted or is biased to a neutral positio'r'i' between opposed magnetic poles. Also, other forms of switching means, carried by the adjusting member, may be provided for actuation by the armature. I intend, therefore, that my invention be limited only by the scope of the appended claims.

I claim as m invention:

1. In an electromagneticallyoperated switch ing device: a core, an energizing coil for all core, an elongated armature mounted for sum lar movement about one of its ends in directiom toward and away from said core and biased in the last-named direction, means limiting the movement of said armature in both of said direction: and comprising a member having spaced-span portions between which the free end portion oi said armature extends, said member being ac movable that said armature is moved therewith in said directions, to position it with respect to the core, a first contact element carried by the free end of said armature, and a second contact element cooperable with said first contact element and mounted on one of said spaced-apart portions.

2. In an electromagnetically operated switching device: a core, an energizing coil for said core, an armature pivoted for movement in directions toward and away from said core and biased in the last-named direction, means limiting the movement of said armature in both 01' said directions and comprising a U-shaped member between the arms of which a portion of said armature is disposed, said U-shaped member having a laterally extending arm mounted for reciprocable movement in directions transverse to the axis of said armature whereby said armature can be moved in said directions to position it with respect to said core, a first contact element carried by said portion or said armature, and a second contact element cooperable with said first contact element and mounted on one 01' the arms of said U-shaped member.

3. In an electromagnetically operated switching device: a U-shaped core; an energizing coil for said core; an elongated armature pivoted at the free end of one arm of said core, and having a portion extending beyond the free end 0! the other of said core arms and movable in directions theretoward and away therefrom; means biasing said armature in said last-named direction; means limiting the movement or said armature in both of said directions and comprising a U-shaped member between the arms of which said extended portion of the armature is disposed; said U-shaped member having a laterally extending arm mounted for reciprocable movement in directions transverse to the axis of said armature, whereby said armature can be moved in said directions to position it with respect to the free end of the other oi said core arms; a first contact element carried by said extended portion of the armature; and a second contact element oooperable with said first contact element and mounted on one of the arms of said U-shaped member.

WILLIAM R. RAY. 

